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chore(unnecessary_map_on_constructor): clean-up

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- reduce indentation
- print constructor/method name in backticks
This commit is contained in:
Ada Alakbarova 2025-11-07 22:13:12 +01:00
parent dddaf0768c
commit 21ddc50eec
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2 changed files with 30 additions and 38 deletions
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52
clippy_lints/src/unnecessary_map_on_constructor.rs
View file

@ -35,18 +35,17 @@ declare_lint_pass!(UnnecessaryMapOnConstructor => [UNNECESSARY_MAP_ON_CONSTRUCTO
impl<'tcx> LateLintPass<'tcx> for UnnecessaryMapOnConstructor {
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx rustc_hir::Expr<'tcx>) {
if expr.span.from_expansion() {
return;
}
if let hir::ExprKind::MethodCall(path, recv, [map_arg], ..) = expr.kind
if !expr.span.from_expansion()
&& let hir::ExprKind::MethodCall(path, recv, [map_arg], ..) = expr.kind
&& !map_arg.span.from_expansion()
&& let hir::ExprKind::Path(fun) = map_arg.kind
&& let Some(sym::Option | sym::Result) = cx.typeck_results().expr_ty(recv).opt_diag_name(cx)
{
let (constructor_path, constructor_item) = if let hir::ExprKind::Call(constructor, [arg, ..]) = recv.kind
&& let hir::ExprKind::Path(constructor_path) = constructor.kind
&& !constructor.span.from_expansion()
&& !arg.span.from_expansion()
{
if constructor.span.from_expansion() || arg.span.from_expansion() {
return;
}
(constructor_path, arg)
} else {
return;
@ -67,29 +66,22 @@ impl<'tcx> LateLintPass<'tcx> for UnnecessaryMapOnConstructor {
_ => return,
}
if let hir::ExprKind::Path(fun) = map_arg.kind {
if map_arg.span.from_expansion() {
return;
}
let mut applicability = Applicability::MachineApplicable;
let fun_snippet = snippet_with_applicability(cx, fun.span(), "_", &mut applicability);
let constructor_snippet =
snippet_with_applicability(cx, constructor_path.span(), "_", &mut applicability);
let constructor_arg_snippet =
snippet_with_applicability(cx, constructor_item.span, "_", &mut applicability);
span_lint_and_sugg(
cx,
UNNECESSARY_MAP_ON_CONSTRUCTOR,
expr.span,
format!(
"unnecessary {} on constructor {constructor_snippet}(_)",
path.ident.name
),
"try",
format!("{constructor_snippet}({fun_snippet}({constructor_arg_snippet}))"),
applicability,
);
}
let mut app = Applicability::MachineApplicable;
let fun_snippet = snippet_with_applicability(cx, fun.span(), "_", &mut app);
let constructor_snippet = snippet_with_applicability(cx, constructor_path.span(), "_", &mut app);
let constructor_arg_snippet = snippet_with_applicability(cx, constructor_item.span, "_", &mut app);
span_lint_and_sugg(
cx,
UNNECESSARY_MAP_ON_CONSTRUCTOR,
expr.span,
format!(
"unnecessary `{}` on constructor `{constructor_snippet}(_)`",
path.ident.name
),
"try",
format!("{constructor_snippet}({fun_snippet}({constructor_arg_snippet}))"),
app,
);
}
}
}

16
tests/ui/unnecessary_map_on_constructor.stderr
View file

@ -1,4 +1,4 @@
error: unnecessary map on constructor Some(_)
error: unnecessary `map` on constructor `Some(_)`
--> tests/ui/unnecessary_map_on_constructor.rs:32:13
|
LL | let a = Some(x).map(fun);
@ -7,43 +7,43 @@ LL | let a = Some(x).map(fun);
= note: `-D clippy::unnecessary-map-on-constructor` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::unnecessary_map_on_constructor)]`
error: unnecessary map on constructor Ok(_)
error: unnecessary `map` on constructor `Ok(_)`
--> tests/ui/unnecessary_map_on_constructor.rs:34:27
|
LL | let b: SimpleResult = Ok(x).map(fun);
| ^^^^^^^^^^^^^^ help: try: `Ok(fun(x))`
error: unnecessary map_err on constructor Err(_)
error: unnecessary `map_err` on constructor `Err(_)`
--> tests/ui/unnecessary_map_on_constructor.rs:36:27
|
LL | let c: SimpleResult = Err(err).map_err(notfun);
| ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Err(notfun(err))`
error: unnecessary map on constructor Option::Some(_)
error: unnecessary `map` on constructor `Option::Some(_)`
--> tests/ui/unnecessary_map_on_constructor.rs:39:13
|
LL | let a = Option::Some(x).map(fun);
| ^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `Option::Some(fun(x))`
error: unnecessary map on constructor SimpleResult::Ok(_)
error: unnecessary `map` on constructor `SimpleResult::Ok(_)`
--> tests/ui/unnecessary_map_on_constructor.rs:41:27
|
LL | let b: SimpleResult = SimpleResult::Ok(x).map(fun);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `SimpleResult::Ok(fun(x))`
error: unnecessary map_err on constructor SimpleResult::Err(_)
error: unnecessary `map_err` on constructor `SimpleResult::Err(_)`
--> tests/ui/unnecessary_map_on_constructor.rs:43:27
|
LL | let c: SimpleResult = SimpleResult::Err(err).map_err(notfun);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try: `SimpleResult::Err(notfun(err))`
error: unnecessary map on constructor Ok(_)
error: unnecessary `map` on constructor `Ok(_)`
--> tests/ui/unnecessary_map_on_constructor.rs:45:52
|
LL | let b: std::result::Result<i32, SimpleError> = Ok(x).map(fun);
| ^^^^^^^^^^^^^^ help: try: `Ok(fun(x))`
error: unnecessary map_err on constructor Err(_)
error: unnecessary `map_err` on constructor `Err(_)`
--> tests/ui/unnecessary_map_on_constructor.rs:47:52
|
LL | let c: std::result::Result<i32, SimpleError> = Err(err).map_err(notfun);